This invention relates to a circuit arrangement comprising a controller for supplying dialling pulses for transmission means.
In DE-OS 32 48 355 is disclosed a circuit arrangement for supplying dialling pulses through a line connected to a current source in a communication facility, more specifically, a telephone facility. The arrangement comprises a dialling pulse generator controlling, via a controller, a contact mechanism inserted into the line. The switching mechanism thereby causes a change in the current passing through the line with each pulse delivered by the pulse generator. The controller is realised as an optocoupler, whereas the switching device connected in series with the line is a field-effect transistor. By means of a supply circuit a loop is formed between the wires a and b of the transmission line. In addition, from the loop current passing through, the supply circuit derives a supply current which is applied to the remaining circuit portions of the communication facility.